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I bought new drums which are 11.03" Dia. x 2.75" Wide but when i search for 11.03" Dia. and/or 92' E150 shoes my only choices are 2.25" wide leaving 1/2" of usable drum width for friction surface, this really bothers me and helped me to understand why many drums have a lip on the inside, most likely caused by using shoes that are not wide enough to fit the drum.
Every search i did for 92' E150 and/or 11.03" shoes came up the same with 2.25" wide shoes so i edited search criteria for 11.00" drum and VOILA 11.00" x 2.75" shoes appear in search results so I got to thinking about which is worse for brake performance, a shoe that is .030" too small in diameter or a shoe that is 1/2" too narrow..
The diameter MUST match. Take a look at the diagram below - if you have a brake shoe that is too small for the drum, it will only make contact at a very small area (if it even fits with the rest of the hardware!). You will have very little braking power. Yes, the shoe will wear in and the contact patch will grow, but it will never be very big, and you will wear through to metal at the center of the shoe long before you start wearing the ends. Yes, I've exaggerated the difference to make the problem more obvious, but don't think that changes things for the better.
I don't know what the story is with your width problem, but there is no room for "close enough" with the diameter of the shoe.
most brake shoes don't have shoe material all the way to the edge of the metal backing the extra 1/4 inch on each side is probably for clearance, brake dust/ other debris in the drum,.. I would forget about trying to fill that last 1/2 inch with the shoe you may find once it is together it won't spin due to binding/interference, also the drum has to go past the backing plate to keep dirt and water out as much as possible.
The .030 is nothing to worry about. There's more than 1/4" adjustment in the slack adjusters. .030 is less than half of a sixteenth inch. The shoe width does matter, but even the correct width shoe is not as wide as the drum, leaving a ridge over time and wear. 1/2" narrower shoe isn't going to work here. With a 2.75" drum, you need at least a 2.5" shoe. These are rear shoes I'm assuming ? They don't do half the work the front brakes do, so they're not absolutely critical in stopping power.
The diameter MUST match. Take a look at the diagram below - if you have a brake shoe that is too small for the drum, it will only make contact at a very small area (if it even fits with the rest of the hardware!). You will have very little braking power. Yes, the shoe will wear in and the contact patch will grow, but it will never be very big, and you will wear through to metal at the center of the shoe long before you start wearing the ends. Yes, I've exaggerated the difference to make the problem more obvious, but don't think that changes things for the better.
I don't know what the story is with your width problem, but there is no room for "close enough" with the diameter of the shoe.
You're way off base here. .030" difference is within the manufacturing tolerances for brake drum diameter. He's likely looking at the max diameter cast into the drums and assuming this is the actual diameter. Even so, there's far more adjustment in the slack adjusters than .030 travel. Even with the correct diameter shoes and drums, the contact patch on the shoes is never the full lining of the shoe.
It's not about the adjustment travel, it's about the curvature of the shoe matching up with the curvature of the drum. But I agree .030 isn't an issue - I misread it as .3.
